Stomach distension may not necessarily be stomach cancer, but it may be caused by indigestion, such as functional dyspepsia, or benign diseases of the stomach, such as chronic gastritis, gastroesophageal reflux disease, gastric ulcer, duodenal ulcer and gastric polyp. In case of gastric cancer, the clinical manifestations are irregular abdominal pain, abdominal distension or persistent abdominal pain with nausea, poor appetite, regurgitation, emaciation, anemia, black stool and other discomforts, and there may be abdominal pressure pain, while benign diseases of stomach do not have abdominal pressure pain or rebound pain. If patients have stomach distension or other upper gastrointestinal discomfort, it is recommended to improve electronic gastroscopy. If lesions are found in the gastric mucosa under electronic gastroscopy, mucosal biopsies should be taken and sent for pathological biopsy, which is the only way to identify whether there is gastric cancer.